The fuel rail should be full and under pressure. If it's now running at idle but won't accelerate, I'd be checking for leaks/tears in the rubber elbow after the MAF. Could be the MAF but if it will idle I wouldn't suspect the plugs, coil, distributor. Sounds mostly like an airflow metering issue or massive vacuum/intake leak. Those rubber elbows will develop cracks deep down in the bellows and you can't spot them unless you take it off and look, engine might idle but when you hit the gas, the engine moves and opens up the crack. Also make sure the clamps at both ends are secure, once you eliminate that there are other things to check if that doesn't fix it.